Quoting Concatenate
In our last note we used wrapr::qe() to help quote expressions. In this note we will discuss quoting and code-capturing interfaces (interfaces that capture user source code) a bit more.
Reusable Pipelines in R
Pipelines in R are popular, the most popular one being magrittr as used by dplyr. This note will discuss the advanced re-usable piping systems: rquery/rqdatatable operator trees and wrapr function object pipelines. In each case we have a set of objects designed to extract extra power from the wrapr dot-arrow […]
Timing Grouped Mean Calculation in R
This note is a comment on some of the timings shared in the dplyr-0.8.0 pre-release announcement. The original published timings were as follows: With performance metrics: measurements are marketing. So let’s dig in the above a bit.
Quasiquotation in R via bquote()
In August of 2003 Thomas Lumley added bquote() to R 1.8.1. This gave R and R users an explicit Lisp-style quasiquotation capability. bquote() and quasiquotation are actually quite powerful. Professor Thomas Lumley should get, and should continue to receive, a lot of credit and thanks for introducing the concept into […]
Running the Same Task in Python and R
According to a KDD poll fewer respondents (by rate) used only R in 2017 than in 2016. At the same time more respondents (by rate) used only Python in 2017 than in 2016. Let’s take this as an excuse to take a quick look at what happens when we try […]
Using a Column as a Column Index
We recently saw a great recurring R question: “how do you use one column to choose a different value for each row?” That is: how do you use a column as an index? Please read on for some idiomatic base R, data.table, and dplyr solutions.
R Tip: Consider radix Sort
R tip: consider using radix sort.
R Tip: Be Wary of “…”
R Tip: be wary of “…“. The following code example contains an easy error in using the R function unique(). vec1 <- c("a", "b", "c") vec2 <- c("c", "d") unique(vec1, vec2) # [1] "a" "b" "c" Notice none of the novel values from vec2 are present in the result. Our […]
wrapr 1.5.0 available on CRAN
The R package wrapr 1.5.0 is now available on CRAN. wrapr includes a lot of tools for writing better R code: let() (let block) %.>% (dot arrow pipe) build_frame() / draw_frame() ( data.frame builders and formatters ) qc() (quoting concatenate) := (named map builder) %?% (coalesce) NEW! %.|% (reduce/expand args) […]
R Tip: Use Slices
R tip: use slices. R has a very powerful array slicing ability that allows for some very slick data processing.